The present invention relates to an air duct construction for a vehicle, and more particularly relates to such an air duct construction for leading air, which has been heated or cooled by a heater or an air conditioner of a vehicle provided in front of the front seat or seats of the vehicle, to the rear seating space thereof.
In a vehicle, which may incorporate a front seating assembly as either a single bench seat or a pair of bucket seats and typically somewhat raised up from the floor of the vehicle to leave an underneath space, a unit for providing air to the interior of the passenger compartment of the vehicle is typically provided in front of the front seating assembly, under the instrument panel of the vehicle, and further is typically centrally located with regard to the transverse dimension of the vehicle. Such a unit may either be an air heater or an air cooler, both of which will be hereinafter referred to as "air treatment unit"; the present invention applies equally to both cases.
During the operation of such an air treatment unit, it injects from its air outlet port or ports heated or cooled air (hereinafter referred to as "treated air") into the passenger compartment of the vehicle, and in the prior art typically this flow of treated air is directed from this outlet port or ports towards the feet of persons seated on the front seating assembly. In such a construction, it is expected that part of this treated air will flow through the aforementioned underneath space under the front seating assembly to reach the space in front of the rear seating assembly of the vehicle, so as to impinge upon the feet of persons seated on the rear seating assembly, and thereafter generally to provide a supply of treated air in the rear seating space of the vehicle. However, these expectations are not always properly fulfilled, because the feet of persons seated on the front seating assembly often obstruct this flow of treated air under the front seating assembly, so that this flow of air does not pass properly towards the rear seating assembly, and in such a case the treating of the air in the rear seating space of the vehicle, and particularly of the air impinging on the feet of persons seated on the rear seating assembly, becomes inadequate. Also, in such a case, the feet of such persons seated on the front seating assembly may suffer because of the overprovision of treated air, and may be overheated or overcooled, thus causing discomfort.
In order to improve the treating of the air in the rear seating space, in the prior art it has been proposed and practiced to provide a special air duct under the upper surface of the floor of the vehicle, for specially leading treated air to the rear seating space, the front end of said air duct being communicated to the air treatment unit and the rear end of said air duct opening to the rear seating space. This flow of treated air thus bypasses the aforesaid underneath space under the front seating assembly. This form of construction is certainly effective for improving the treating characteristic of the air in the rear seating space, but it has the disadvantage that such a special air duct is required to be quite long, and accordingly its provision is costly. Moreover the available space for persons within the passenger compartment of the vehicle is reduced, because the upper surface of the floor of the vehicle is required to be raised up in order to accomodate such an air duct. The convenience of the arrangements within the passenger compartment is also deteriorated, because it is difficult to form the upper surface of the floor as flat.